Speedo Fastskin FS II did not reduce drag, say scientists (now)

Researching how toothlike scales on sharks reduce drag by generating vortexes on the front edge of the skin, eddies that essentially would suck the shark forward, Harvard University bioroboticist George Lauder and graduate student Johannes Oeffner at Lauder Lab also looked at shark-skin mimics like the Speedo Fastskin II fabric and silicon rubber “riblets” used on America’s Cup sailing boats in 1987.

Although the riblets improved the flexible foil’s swimming speed by 7.2 percent, the Speedo fabric apparently had no effect at all, perhaps because its bumps were small, rounded and very widely spaced compared with both shark denticles and the sharp-edged riblets. (Lauder did note that figure-hugging Fastskin swimming costumes probably enhance the swimmer’s performance in other ways.)